A method of modelling a wind oxidation zone of an open pit mine

Abstract

The present application relates to a kind of open pit wind oxidation area modeling method, the purpose is to solve the problem of wind oxidation area in mining area, no coal area, and local coal seam wind oxidation, guide mining design, reduce invalid stripping and other technical problems, technical scheme is as follows: it includes the following steps: define database structure, establish geological database, determine weathering interface and oxidation interface and virtually a weathering oxidation surface, establish weathering oxidation surface model and coal seam surface model, weathering oxidation surface model and coal seam surface model carry out Boolean mathematical operation, draw coal seam thickness contour line;The present application can reasonably control the coal seam thickness contour line with mining value by constructing the method of virtual weathering oxidation interface, reduce the invalid stripping of wind oxidation area in mining area, save production cost, improve economic benefit.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of mining engineering, and specifically relates to a modeling method for a wind oxidation area of an open-pit mine. BACKGROUND

[0002] The wind oxidation area of a coal seam is often affected by various geological factors, such as geological structure, groundwater activity, and surface conditions. In the process of geological modeling, accurately identifying and describing these factors and their impact on the wind oxidation of the coal seam is the key to ensuring the accuracy of the geological model. By controlling the wind oxidation area of the coal seam, the preservation state and mining conditions of the coal seam can be more effectively predicted, providing reliable geological basis for subsequent coal mining.

[0003] A geological model is not only the basis for coal mining, but also an important tool for optimizing mining planning. If the control of the wind oxidation area of the coal seam is ignored in the process of geological modeling, it may lead to unreasonable mining planning, which will affect the production efficiency and safety of the coal mine. Therefore, by accurately controlling the wind oxidation area of the coal seam, the mining layout can be optimized, the safety hazards in the mining process can be avoided, and the overall economic benefit of the coal mine can be improved.

[0004] In the past, the impact of coal weathering and oxidation on mining and production was not considered in geological modeling. Geological modeling not only focuses on the spatial distribution and morphology of the coal seam, but also on the quality and availability of the coal seam. By controlling the wind oxidation area of the coal seam, the quality and utilization value of the coal seam can be more accurately evaluated, providing a scientific basis for the rational utilization of coal resources. This helps to realize the sustainable development and utilization of coal resources and promotes the green development of the coal industry. SUMMARY

[0005] The purpose of the present application is to solve the above problems and provide a modeling method for a wind oxidation area of an open-pit mine.

[0006] To solve the technical problem, the technical solution adopted by the present application is as follows:

[0007] A modeling method for a wind oxidation area of an open-pit mine, comprising the following steps:

[0008] Step 1) Define the database structure and establish the geological database

[0009] Step 1.1) Collect and organize the original drilling data: obtain the position, depth, lithology description, coal seam roof and floor position, weathering layer position and oxidation layer position information of the drilling;

[0010] Step 1.2) Define the database structure:

[0011] The database structure includes three tables: positioning table, inclinometer table and lithology table;

[0012] The positioning table describes the drilling position and depth, the inclinometer table describes the drilling inclinometer, and the lithology table describes the lithology position and weathering horizon position;

[0013] Step 1.3) using a special software for geological modeling: arranging the original data into an EXCEL table, and importing the data into a geological database by using a geological modeling software;

[0014] Step 2) determining the weathering interface and oxidation interface, and virtually the weathering-oxidation surface

[0015] In the geological modeling of a mining area, the weathering interface and the oxidation interface are two important concepts;

[0016] The weathering interface refers to the limit of the rock and coal seam below the ground surface affected by weathering, and all the rock and coal seams above the interface are weathered;

[0017] The oxidation interface is located below the weathering interface, and the coal seam above the interface is considered as oxidized coal, and the weathered and oxidized coal has no utilization value;

[0018] The weathering interface, the oxidation interface and the oxidation zone between them are virtually a weathering-oxidation surface, and the theoretical coal seam entity is separated into two parts: the coal seam above the weathering-oxidation surface is considered as weathering-oxidation coal, and the coal seam below the weathering-oxidation surface is considered as coal with mining value;

[0019] Step 3) establishing a weathering-oxidation surface model and a coal seam surface model

[0020] Step 3.1) extracting the bottom interface data of the weathering-oxidation surface: extracting all the bottom interface data points related to the weathering-oxidation surface from the geological database in step 1);

[0021] Step 3.2) establishing a weathering-oxidation surface model: performing Kriging interpolation modeling on the bottom interface data points extracted in step 3.1) by using the modeling software grid estimation, generating a three-dimensional surface model of the weathering-oxidation surface, and using uniform grid + control point method for interpolation, and the established surface is smooth and controlled by control points;

[0022] Step 3.3) establishing a coal seam surface model: using the roof and floor data points of the coal seam, and performing Kriging interpolation on the coal seam surface model by using the modeling software grid estimation; the coal seam "surface model" refers to the top and bottom surface model of the original coal seam, which includes the weathering and oxidation horizon;

[0023] Step 4) performing Boolean mathematical operation on the weathering-oxidation surface model and the coal seam surface model

[0024] Step 4.1) performing Boolean operation on the weathering-oxidation surface A and the coal seam roof surface B and the coal seam floor surface C respectively and taking the lower cutting surface;

[0025] The lower cutting surface D1 coal seam roof cutting surface is obtained by performing a Boolean operation on the weathered and oxidized surface A and the coal seam roof surface B, and the lower cutting surface D2 coal seam floor cutting surface is obtained by performing a Boolean operation on the weathered and oxidized surface A and the coal seam floor surface C.

[0026] Step 4.2) performing mathematical operation on the cutting coal seam roof surface D1 and the coal seam floor surface D2 to obtain a normal coal seam thickness surface, i.e. a good coal seam thickness surface model E=D1-D2 after removing weathered and oxidized coal;

[0027] Step 4.3) generating a thickness contour by using the good coal seam thickness surface model E=D1-D2 obtained in step 4.2) to intuitively display the distribution of the coal seam.

[0028] Further, the weathered horizon and the oxidized horizon in step 2) are determined by using any one of drilling records, geophysical well logging and coal seam sampling and testing.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] The present application can reasonably control the weathered interface and the oxidized interface by constructing a virtual weathered and oxidized surface, establish a fast, intuitive and accurate geological model to guide production, reduce the invalid stripping in the weathered and oxidized area of the mine, save production cost and improve economic benefit. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 The table is used for inputting drilling data of the present application.

[0032] Figure 2 The figure is a schematic diagram of the weathered and oxidized surface of the present application.

[0033] Figure 3 The figure is a schematic diagram of the weathered and oxidized surface performing a Boolean operation when passing through the coal seam of the present application.

[0034] Figure 4 The figure is a schematic diagram of the weathered and oxidized surface above the coal seam of the present application.

[0035] Figure 5 The figure is a schematic diagram of the weathered and oxidized surface below the coal seam of the present application.

[0036] Figure 6 The figure is a coal seam thickness contour map of the coal seam thickness surface obtained by the present application. DETAILED DESCRIPTION

[0037] The present application will be further described below in combination with the drawings.

[0038] 1. A weathered and oxidized area modeling method of an open-pit mine, characterized in that the method comprises the following steps:

[0039] Step 1) Define database structure, build geological database

[0040] Step 1.1) Collect and organize original drilling data: obtain drilling location, depth, lithology description, coal seam roof and floor location, weathering horizon and oxidation horizon information;

[0041] Step 1.2) Define database structure:

[0042] The database structure includes three tables: location table, inclinometer table and lithology table;

[0043] The location table describes the drilling location and depth, the inclinometer table describes the drilling inclinometer, and the lithology table describes the lithology location and weathering horizon location;

[0044] Step 1.3) Use geological modeling software: organize the original data into EXCEL tables, and use geological modeling software to import the data into the geological database, as shown in Figure 1

[0045] Step 2) Determine weathering interface and oxidation interface, and virtually weathering-oxidation surface

[0046] Due to tectonic and topographic reasons, overburden in the mining area is weathered, and part of the upper layer or even the entire layer is weathered and oxidized. In the geological modeling of the mining area, the weathering interface and the oxidation interface are two important concepts;

[0047] The weathering interface refers to the limit of the rock and coal seam below the surface affected by weathering. All rock and coal seams above this interface are weathered;

[0048] The oxidation interface is located below the weathering interface. The coal seam above this interface is considered to be oxidized coal. Weathered and oxidized coal do not have utilization value;

[0049] The weathering horizon and oxidation horizon are determined by drilling records. The weathering interface, oxidation interface and oxidation zone between them are virtually a weathering-oxidation surface, as shown in Figure 2 The coal seam entity is divided into two parts: the coal seam above the weathering-oxidation surface is considered to be weathered and oxidized coal, and the coal seam below the weathering-oxidation surface is considered to be coal with mining value;

[0050] Step 3) Build weathering-oxidation surface model and coal seam surface model

[0051] Step 3.1) Extract the bottom interface data of the weathering-oxidation surface: extract all bottom interface data points related to the weathering-oxidation surface from the geological database in step 1);

[0052] ​Step 3.2) Establishing the weathered and oxidized surface model: the data points of the bottom interface extracted in step 3.1) are subjected to Kriging interpolation modeling by using the modeling software grid evaluation, and a three-dimensional surface model of the weathered and oxidized surface is generated, the interpolation adopts the uniform grid + control point method, and the surface is smooth and controlled by the control points;

[0053] Step 3.3) Establishing the coal seam surface model: using the roof and floor data points of the coal seam, the coal seam surface model is established by Kriging interpolation using the modeling software grid evaluation; the coal seam "surface model" refers to the top and bottom surface model of the original coal seam, which includes the weathered and oxidized horizon;

[0054] Step 4) Boolean mathematical operation on the weathered and oxidized surface model and the coal seam surface model

[0055] Step 4.1) Boolean operation of the weathered and oxidized surface A with the coal seam roof surface B and the coal seam floor surface C respectively, and taking the lower cutting surface;

[0056] The Boolean operation of the weathered and oxidized surface A with the coal seam roof surface B takes the lower cutting surface D1 coal seam roof cutting surface, and the Boolean operation of the weathered and oxidized surface A with the coal seam floor surface C takes the lower cutting surface D2 coal seam floor cutting surface;

[0057] Step 4.2) Mathematical operation of the cutting coal seam roof surface D1 and the cutting coal seam floor surface D2 to obtain the normal coal seam thickness surface, that is, the good coal seam thickness surface model E=D1-D2 after removing the weathered and oxidized coal;

[0058] As shown in Figure 3 , when the weathered and oxidized surface A passes through the coal seam, the Boolean operation of the weathered and oxidized surface A with the coal seam roof surface B and the coal seam floor surface C respectively takes the lower cutting surface to obtain the coal seam roof cutting surface D1 and the coal seam floor cutting surface D2, and then the good coal seam thickness surface E=D1-D2 after removing the weathered and oxidized coal;

[0059] As shown in Figure 4 , when the coal seam roof surface B and the coal seam floor surface C are both located below the weathered and oxidized surface A, it is considered that the coal seam is of mining value, and the thickness of the coal seam is E=B-C;

[0060] As shown in , when the coal seam roof surface B and the coal seam floor surface C are both located above the weathered and oxidized surface A, it is considered that the coal seam is weathered and oxidized coal and has no utilization value;

[0061] Figure 5 As shown in

[0062] According to the model, the lower cutting surface is obtained by performing a Boolean operation on the wind-oxidized surface A and the coal seam roof surface B and the coal seam floor surface C, the coal seam roof cutting surface D1=A and the coal seam floor cutting surface D2=A, and the thickness of the coal seam E=D1-D2=A-A=0, which indicates that the coal seam has no utilization value, and the calculation result of the model is the same as the actual situation.

[0063] The determination of the wind-oxidized interface can be made through drilling records, geophysical well logging, and coal seam sampling and testing, and the virtual wind-oxidized surface method can be used to reasonably control the boundary of the wind-oxidized area, and the application effect is remarkable.

[0064] Step 4.3) The thickness surface model of the good coal seam after removing the wind-oxidized coal obtained in step 4.2) is used to generate a thickness contour by using modeling software, so as to intuitively display the distribution of the coal seam.

[0065] The determination of the weathered horizon and the oxidized horizon in step 2) can also use any one of geophysical well logging or coal seam sampling and testing.

[0066] Through the above steps, the geological model of the wind-oxidized area of the open-pit mine can be effectively established, which provides a scientific basis for the mining and management of the mine.

[0067] As shown in Figure 6 : the yellow area is the wind-oxidized area (i.e. full-layer wind oxidation), and the thickness of the good coal gradually increases from 0 meters (i.e. partial wind oxidation).

Claims

1. A method of modelling a wind oxidation zone of an open pit mine, characterised by, Comprising the following steps: Step 1) defining the database structure, establishing the geological database Step 1.1) collecting and sorting the original drilling data: obtaining the position, depth, lithology description, coal seam roof and floor position, weathering horizon and oxidation horizon information of the drilling; Step 1.2) defining the database structure: The database structure includes three tables: positioning table, inclinometer table and lithology table; The positioning table describes the drilling position and depth, the inclinometer table describes the drilling inclinometer, and the lithology table describes the lithology position and weathering horizon position; Step 1.3) using geological modeling software: sorting the original data into EXCEL table, using geological modeling software to import the data into the geological database; Step 2): determining the weathering interface and oxidation interface, and virtually weathering and oxidation surface In the mine area geological modeling, weathering interface and oxidation interface are two important concepts; The weathering interface refers to the limit of the rock and coal seam below the ground surface affected by weathering, and all the rock and coal seam above the weathering interface are weathered; The oxidation interface is located below the weathering interface, and the coal seam above the oxidation interface is considered as oxidized coal, and the weathering and oxidized coal do not have utilization value; The weathering interface, oxidation interface and oxidation zone between them are virtually weathered and oxidized surface, and the theoretical coal seam entity is separated into two parts: the coal seam above the weathering and oxidation surface is considered as weathered and oxidized coal, and the coal seam below the weathering and oxidation surface is considered as coal with exploitation value; Step 3): establishing the weathering and oxidation surface model and the coal seam surface model Step 3.1) extracting the bottom interface data of the weathering and oxidation surface: extracting all the bottom interface data points related to the weathering and oxidation surface from the geological database in step 1); Step 3.2) establishing the weathering and oxidation surface model: using the bottom interface data points extracted in step 3.1) to perform Kriging interpolation modeling by using the modeling software grid estimation, generating a three-dimensional surface model of the weathering and oxidation surface, and using uniform grid + control point method for interpolation, the established surface is smooth and controlled by control points; Step 3.3) establishing the coal seam surface model: using the roof and floor data points of the coal seam to perform Kriging interpolation to establish the coal seam surface model; the coal seam "surface model" refers to the top and bottom surface model of the original coal seam, which includes weathering and oxidation horizon; Step 4): performing Boolean mathematical operation on the weathering and oxidation surface model and the coal seam surface model Step 4.1) performing Boolean operation on the weathering and oxidation surface A and the coal seam roof surface B, coal seam floor surface C respectively and taking the lower cutting surface; The weathering and oxidation surface A and the coal seam roof surface B are subjected to Boolean operation to take the lower cutting surface D1 coal seam roof cutting surface, and the weathering and oxidation surface A and the coal seam floor surface C are subjected to Boolean operation to take the lower cutting surface D2 coal seam floor cutting surface; Step 4.2) performing mathematical operation on the cutting coal seam roof surface D1 and floor surface D2 to obtain the normal coal seam thickness surface, that is, the good coal seam thickness surface model E=D1-D2 after removing the weathered and oxidized coal; Step 4.3) using the good coal seam thickness surface model obtained in step 4.2) to generate the thickness contour by using the modeling software, so as to intuitively display the distribution of the coal seam.

2. A method of modelling a wind oxidation zone of an open pit mine according to claim 1, characterised in that, The step 2) determines the weathered layer and the oxidized layer by using any one of the drilling record, the geophysical well logging and the coal seam sampling test.

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